초록 close

The concept of no cost zone(NCZ) is induced for introduction of operation policy considering moving characteristic of S/R machine in case that are varied with the position of I/O points. In this study, we compared the efficiency of NCZ operation policy with the policy of random retrieval, retrieval from the closest output point, retrieval by the sequence of the longest waiting time, close range retrieval, and retrieval by due date. We simulated each operation policy to compare their performance by the help of computer simulation package GPSS/EMS. We found that the NN(nearest neighbour) has much more efficiency than other policy in terms of turnaround time and the policy of retrieval by the sequence of the longest waiting time is the best policy in the perspectives of performance among considered operation policies when the position of I/O point are separated.